CORTLAND — Mark Sanchez is eyeing a fourth-year breakthrough similar to the one had by Eli Manning — a season that ended with a Syper Bowl MVP.

That might well be viewed as a leap of faith, and not solely by Tim Tebow.

Manning started more games at Mississippi than Sanchez did at USC for starters. Manning had a pre-Glock Plaxico Burress in his prime and a wise old Amani Toomer, who ostensibly wouldn’t offer the opinion that Sanchez is better than Manning.

But you have to admit Sanchez looks like a different guy, in all ways, this summer. Emotionally, he hasn’t blinked at the presence of Tebow. And physically, well, we haven’t seen him shirtless yet, we haven’t seen him take any hits yet, but he has never looked this sturdy, this prepared to stand up to the 290-pound predators looking to take his head off when Roger Goodell isn’t looking.

And so, while Tebow holds the ball and holds it some more and never stops trying to make his delivery more compact and his throws more accurate, as the notion of quarterback controversy here and now has been exposed as wholly myth, my message to Jets fans, pro-Tebow and otherwise, is this:

Pray that Sanchez stays healthy.

The biggest reason Sanchez can talk ambitiously about taking that step he never took last season — aside from Tony (Tempo) Sparano replacing Brian Schottenheimer as offensive coordinator — is that a bad throwing shoulder across the latter stages of the season sabotaged him.

This doesn’t come from him, of course. It came recently from Burress.

And yesterday it came from Dustin Keller.

“I think at times he was hurting pretty bad, but he did a good job of working through it,” Keller told The Post.

How could you tell that he was hurting pretty bad?

“You could usually tell by the amount of time a guy’s spending in the training room,” Keller said. “So I know he was always in there getting his shoulder worked on and all that. But he never complained about it and he always worked through it.”

Sanchez suffered in silence.

“I don’t think anybody really knew about it.” Keller said. “Obviously he would let the trainers know, but anybody outside of that would never know just because he played through it and he would just tough through those things. He did a good job of playing through it on gamedays, ’cause I think most people couldn’t even tell that he had a shoulder injury.”

Sanchez is a muscle-packed 230 pounds these days. He ended 2011 a battered and bruised 218. He was listed as probable with a neck injury in Week 12, and again in Weeks 15 and 16.

“I think more than anything, it will help him take in all the hits that he will throughout the season, just to be able to stay healthier longer,” Keller said.

Sanchez is no excuse-maker.

“By the end of the season, everybody’s banged up a little bit, so I have no excuse for the way I played,” he said. “Whether your shoulder, your back, your knee, whatever, your ankle, whether anything hurts, that decisions and preparation … ”

In the meeting room with Sanchez, it may as well be Jets East.

“He’s very in tune,” Keller said. “He knows what everybody’s doing on every single play, and that’s what you expect of your quarterback.”

Sanchez clearly studied the playbook and he studied Manning’s career arc and couldn’t help but notice how he weathered the storm. Manning’s numbers didn’t change drastically in his fourth season, but he flourished in the playoffs.

Tebow may have made strides but he remains a Wing and a Prayer.

“You just want more accuracy and get it out faster, so hopefully, that’s happening,” Tebow said.

Sparano was perturbed on one particular third-and-medium pass.

“I was trying to throw the post, and I was supposed to take the checkdown,” Tebow said.

Tebow laughs about the attention his shirtless romp in the rain has received, vows never to change who he is, as much as he yearns sometimes for a normal life, for a carefree night out on the town, any town, any church. When his group interview ends, he says, “Thanks y’all.”